Found a Slakoth this morning in my neighborhood! I'm now walking it to get extra candies. Need to find a Ralts too. Hopefully either can be found at nests.
Granted, this is based a lot on where you're at, but I don't think Slakoth is going to be very rare. I've already caught a few, and the only others I've seen/caught have been obviously common types (Wurmple, Seedot, Gulpin, Zigzagoon).
Anyway, coming from a player who hates raids (I'm in a mid-size city and largish metropolitan area but we aren't a pedestrian friendly region) and is underwhelmed by the slow roll out of a new generation, the best factor for me is actually the weather system, or its by-product. I'm in NE Ohio so we might hit 4-5 different weather biomes in an afternoon, which is great for diverse types showing up, but it's the weather-enhanced Pokémon that I'm loving. I've already caught an 89% Eevee at 7000 stardust and a few other, less exciting types in the same range. I'm actually looking to catch stuff I'd usually pass up just for the chance of getting a more powerful one off the bat.
To add to others' pain, I'm someone who barely does raids (1-2 a week depending on if a gym has one going on I can solo by parking nearby) and have no legendaries from them for aforementioned reasons, yet in early November I got an EX Raid for Mewtwo and got that.